Background Information• “Does human verbal interaction with plants affect

their growth?”• Non-scientific anecdotal evidence claims that

plants that are “talked to” grow faster.• Two possible reasons.• Several scientific studies have already

researched this phenomenon.

Why Does This Happen?

• The scientific theory: excess carbon dioxide and/or vibrations from sound waves.

• The metaphysical theory: plants respond to human emotional cues

Research• Music Genre study by students at Miami

University (Wichman).• South Korean study: playing Beethoven for rice,

“plant genes that can 'hear'” (Fleming).• Prince Charles talked to plants (Stevenson).• “Positive Music” (Robertson).• Mythbusters episode.

Experiment Planning• Hypothesis: “If a plant can receive a significant

amount of carbon dioxide (CO2) and vibrations from a human voice, this surplus can contribute to better than average growth.”

• Prediction: “Therefore, the 'Yelling' groups should exhibit more growth than the 'Whispering' groups, which, in turn, should exhibit more growth than the excess-CO2-deficient music groups.”

Marigolds

• Genus Tagetes, 56 species, (e.g. Calendula, Lucida, Minuta).

• In the Sunflower (Asteraceae) family.• Dicot with pinnately compound

leaves.• Usually orange flowers, can vary

from gold to red.• Native to the Americas, naturalized

around the world.

Marigolds

Test Groups• Group A: Control• Group B: Whispering• Group C: Yelling• Group D: Recorded

Music

• 5 potted marigold seedlings per group

• 10 minute treatments daily (Mon-Thurs)

• Planted 2/1/11, • Finished Trials 3/7/11.

Variables• Controlled Variables: amount of sunlight, water,

seeds per pot, dirt, size of pot, time period.• Experimental Variables: sound exposure, carbon

dioxide exposure.• Measurement Criteria: vertical growth (cm) over

time (weeks), number of leaves/buds (at end).

Group A: ControlPlant # Height

(cm) on 2/7/11

Height (cm) on 2/14/11

Height (cm) on 2/28/11

Height (cm) on 3/7/11

# of leaves

1 0.9 1.8 2.7 2.5 6

2 1.7 2.0 3.2 3.0 6

3 n/a 1.4 2.1 3.1 6

4 1.3 1.9 2.3 2.2 6

5 n/a 1.2 2.0 2.6 5

Average 1.30 1.66 2.46 2.68 6

Group B: WhisperingPlant # Height

(cm) on 2/7/11

Height (cm) on 2/14/11

Height (cm) on 2/28/11

Height (cm) on 3/7/11

# of leaves

1 1.5 1.7 2.6 3.4 6

2 n/a 0.6 1.3 2.5 6

3 1.4 2.0 2.7 1.6 6

4 0.8 1.2 2.8 3.6 6

5 1.2 1.6 3.3 3.5 6

Average 1.23 1.42 2.54 2.92 6

Group C: YellingPlant # Height

(cm) on 2/7/11

Height (cm) on 2/14/11

Height (cm) on 2/28/11

Height (cm) on 3/7/11

# of leaves

1 1.8 2.0 n/a n/a died

2 0.9 1.8 2.5 3.0 6

3 1.8 1.9 3.3 3.8 6

4 1.7 3.0 4.5 4.7 6

5 0.6 2.0 2.3 2.4 6

Average 1.36 2.14 3.15 3.48 6

Group D: Recorded MusicPlant # Height

(cm) on 2/7/11

Height (cm) on 2/14/11

Height (cm) on 2/28/11

Height (cm) on 3/7/11

# of leaves

1 0.7 1.5 2.2 2.3 6

2 n/a 1.6 2.0 2.2 6

3 n/a 0.8 1.7 1.8 6

4 1.4 2.3 3.4 3.8 6

5 n/a 1.0 2.0 2.0 6

Average 1.05 1.44 2.26 2.42 6

Analysis• Did our hypothesis pass the test?• Contradictions?

2/7 2/14 2/21 2/28 3/70

0.5

1

1.5

2

2.5

3

3.5

4

Vertical Growth over Time

Control (A)Whispering (B)Yelling (C)Music (D)

Time (week)

Hei

ght (

cm)

Comparing Studies• Music Genre study by students at Miami

University (Wichman).• South Korean study: playing Beethoven for rice,

“plant genes that can 'hear'” (Fleming).• Prince Charles talked to plants (Stevenson).• “Positive Music” (Robertson).• Mythbusters episode.

Room for Improvement• Better sunlight position• Consistent watering/treatments• Faster growing plant species?• Emotional/metaphysical aspect

Any Questions?

Works Cited• Fleming, Nic. "Beethoven can help crops grow more quickly." The Telegraph,

30 Aug 2007. Web. 24 Jan 2011. <http://www.telegraph.co.uk/earth/earthnews/3305158/Beethoven-can-help-crops-grow-more-quickly.html>.

• "Exploding House ('Talking to plants' segment)." Mythbusters. Discovery Channel: 16 Nov 2004. Television. 24 Jan 2011. <http://www.youtube.com/watch?v=CMiVNPXR5qw>.

• Robertson, Don. "About Positive Music." DoveSong, 5 Oct 2005. Web. 24 Jan 2011. <http://www.dovesong.com/positive_music/plant_experiments.asp>.

• Stevenson, Alexa. "Probing Question: Does talking to plants help them grow?." Physorg, 4 Sep 2008. Web. 24 Jan 2011. <http://www.physorg.com/news139763645.html>.

• Wichman, Maggie, et al. "final 1 Plant Stimulus Project." Miami University, 11 Dec 1998. Web. 24 Jan 2011. <http://jrscience.wcp.muohio.edu/nsfall98/FinalArticles/final1PlantStimulusProjec.html>.